help with cloudstack networking

we setup our basic cloudstack using a public network for both the private and public steps of the pod setup and everything runs ok. we can get the secondary storage to talk to the management server and create ISOs and templates fine, but if we setup the pod with a private network ie 192.168.200.1 we cannot get the secondary storage to communicate with the management server, can not start the virtual router or get templates going. can anyone explain why this is? do we have to have a real gateway on the private portion of the pod setup? can anyone help explain this step? thanks for your time.